Can we use data without activating the internet?

The short answer is Yes, if you do not activate internet connection on your mobile phone or tablet or wi-fi modem you will not be able to access the internet. 

But at the same time  if you want to use the wireless technology of the internet, then you will be able to use the internet on your mobile. If you have any experience like this then you can share with us at our gmail at developergang1@gmail.com for the niche Technology Business Write For Us.